So normally, if your EVO X is down on power there is probably a boost leak or maybe even a vacuum leak and worst case something wrong with your wastegate/turbo.

My evo x gsr was driving like a basic lancer all of the sudden with no check engine light
I wasted alot of time taking my car apart and even tried to take the turbo apart because I couldnt figure out whats wrong with my car. So I hope this thread will help any future fellow member who already checked the list below and still cant figure out why.


All intercooler pipes are connected.
I checked the FPR hose
I checked the Fuel pump fuse
I checked the coldside of the turbo to make sure its not seized.
I checked the Wastegate connector rod
Scan for OBD codes

AND IN THE END ... my issue was my AMS HFC has failed with only 15k miles!! So beware .... my HFC material travelled down my exhaust and clogged it up!! If you have this issue, you will notice your exhaust sound is quieter when you start your car.

Wow never have seen this yet before

holy moly. that is nuts.

looks like you just got a free upgrade to a test pipe, lol wow thats nuts, contact ams see if they will warranty it for you,

Never in all my days have I seen anything like that before. Enjoy the new test pipe!

Holy sh*t!

Also, for a bit there I thought you had gone ***** to the wall trying to figure this out and torn apart the car with pieces (like the rear subframe) just sitting on the ground. Then realized the photo was upside down!

First time I have seen one unravel. Have seen some of the smaller units internals become dislodged and get stuck downstream resulting in the same issue. I am selling a Apexi JDM HFC if interested.

AMS basically told me vibrant makes the hfc material so its not AMS' fault and they cant warranty it because its over 1 year old. If they cannot stand behind their products and I cannot recommend them to anyone.

Dam that sucks.

lol, it's like your Evo has a tapeworm!

Or I was thinking kind like.........

I've seen HFC elements fail and create this same problem at least 10 times now.

First time I have seen it unravel like this though... hahah

Guess this answers my dilemma of HFC or TP with resonator.

Happens alot on other platforms....but yeah, it usually just clogs up real good, car feels like poop and thats it. You literally pinksocked that HFC......test pipe time?

Wow that's crazy. Especially that it's AMS too.